Simplify the following expression: $a = \dfrac{-7z + 2}{2z + 3} \div \dfrac{1}{5}$
Explanation: Dividing by a number is the same as multiplying by its inverse. $a = \dfrac{-7z + 2}{2z + 3} \times \dfrac{5}{1}$ When multiplying fractions, we multiply the numerators and the denominators. $a = \dfrac{(-7z + 2) \times 5} {(2z + 3) \times 1}$ $a = \dfrac{-35z + 10}{2z + 3}$